Docs: caught up with v0.13.0 to v0.19.0

The documentation had kept up feature page by feature page and nowhere
else. Now also:

- the home page's App cards (notes of any size, pictures, sharing) and its
  note (the Shell, the VPN, the screenshot key);
- the guide: VPN in the Status Bar and in Settings, the three keys that work
  everywhere, screenshots of the Shell, a picture, sharing, the VPN page and
  the help panel;
- three how-tos: move files with your phone, set up the VPN, take a
  screenshot; where the files are and what things cost in memory;
- the FAQ: screenshots, and what listens on the network;
- the README's opening: what the firmware does today;
- the glossary: Tunnel, Sharing, Screenshot;
- every milestone's status line, with the version each thing shipped in.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT

site/content/howto/_index.md

@@ -1,6 +1,6 @@
 +++
 title = "How-tos"
-description = "Short recipes for things you will want to do: put a file on the card, record a track, capture radio packets, and what to try when something does not work."
+description = "Short recipes for things you will want to do: move files with your phone, set up the VPN, take a screenshot, record a track, capture radio packets, and what to try when something does not work."
 template = "guide-index.html"
 page_template = "guide-page.html"
 sort_by = "weight"

site/content/howto/not-enough-memory.md

@@ -20,6 +20,18 @@ Opening a Gemini page fails with *not enough memory: stop IRC or retry*. Or an u
 
 The [System App](/guide/system/)'s **Memory** view shows free memory, the lowest since the device started, and the largest free block, drawn against the three memory floors (55, 40 and 20 KB). Watch it fall when a connection opens, and recover when it closes.
 
+## What the other things cost
+
+Small next to a secure connection, but they add up when memory is already short:
+
+| | While it is in use |
+|---|---|
+| A note open in the editor, whatever its size | 17 KB |
+| Sharing the card with a browser | 13 KB |
+| The Shell | 7 KB |
+| The VPN tunnel | under 2 KB |
+| Showing a PNG | one free block of 32 KB, while it is decoded |
+
 ## Why it happens
 
 The Cardputer's chip has no extra memory (no PSRAM). A secure (TLS) connection costs about **52 KB** at its peak, and IRC's own connection holds about 40 KB of the 107 KB there is. A second secure connection on top does not fit, so the firmware refuses it early instead of crashing. This is also why IRC steps aside during an update, and why the daily update check waits until IRC is not connected: see [Updates](/guide/updates/).

site/content/howto/phone-files.md

@@ -0,0 +1,30 @@
++++
+title = "Move files with your phone"
+description = "Open the SD card in your phone's browser, over Wi-Fi: download what the device wrote, upload what it needs. Nothing to install."
+weight = 9
+[extra]
+tag = "SD card"
++++
+
+The phone and the Cardputer must be on the **same Wi-Fi network**.
+
+1. On the Cardputer, open **Storage** and press <kbd>w</kbd>. You should see a QR code, an address and a six-digit code.
+2. On the phone, **scan the QR code** with the camera and open the link. The page opens on the card's folders. (Without a camera: type the address in a browser, then the code.)
+3. **To download:** tap a folder to go in, tap a file to download it.
+4. **To upload:** go to the folder you want, tap **Upload files** and pick one or several. A bar shows the progress; if a file with that name is there already, the page asks before replacing it.
+5. **New folder** and **Delete** do what they say. A folder must be empty to be deleted.
+6. On the Cardputer, press Back. Sharing stops, and the code is no longer good.
+
+## What to expect
+
+- About **200 KB a second**: a 3 MB photo takes a quarter of a minute.
+- **One thing at a time.** While a big file moves, the page waits.
+- The device's screen shows how much has gone in and out, and the last thing that was asked.
+
+## Good to know
+
+- **It is not encrypted.** Use it on a network you trust, or [through the VPN](/guide/vpn/).
+- Five wrong codes close it for a minute.
+- It works from a computer's browser too.
+
+More in [Storage: From a phone](/guide/storage/#from-a-phone).

site/content/howto/screenshot.md

@@ -0,0 +1,18 @@
++++
+title = "Take a screenshot"
+description = "Save what the screen shows as a picture, look at it on the device, and get it onto your phone."
+weight = 11
+[extra]
+tag = "Screen"
++++
+
+1. On any screen, press <kbd>Fn</kbd> + <kbd>p</kbd>. A [Toast](/guide/basics/#toasts) says "Screenshot saved in /screenshots". The Toast itself is never in the picture; a dialog or the help panel that is open is.
+2. **To look at it on the device:** open **Storage**, go into `screenshots` and press <kbd>Enter</kbd> on the file. <kbd>Enter</kbd> again shows it at its own size.
+3. **To get it out:** in Storage press <kbd>w</kbd> and [open the card in your phone's browser](/howto/phone-files/); the pictures are in `screenshots`.
+
+## Good to know
+
+- It needs an SD card.
+- The files are PNGs of 240 by 135 pixels, named by date and time.
+- **It refuses on Settings → Debug Console**, the page that shows the console's token: a picture of it would be a copy of the token.
+- From the [Shell](/guide/shell/), `screenshot 5` takes the picture five seconds later, for a screen you can't press keys on.

site/content/howto/sd-files.md

@@ -6,7 +6,7 @@ weight = 2
 tag = "SD card"
 +++
 
-Everything the firmware writes goes in a folder at the top of the card. Switch the Cardputer off, take the card out and read it in a computer; or look at the same folders in the [Storage App](/guide/storage/).
+Everything the firmware writes goes in a folder at the top of the card. To get at it: look at the folders in the [Storage App](/guide/storage/); or [open the card in your phone's browser](/howto/phone-files/), with nothing to install; or switch the Cardputer off, take the card out and read it in a computer.
 
 | What | Where | Kind of file |
 |---|---|---|
@@ -19,7 +19,8 @@ Everything the firmware writes goes in a folder at the top of the card. Switch t
 | Gemini bookmarks | `/gemini/bookmarks.gmi` | gemtext |
 | Files saved from Gemini that are not text | `/gemini/downloads` | whatever they were |
 | Update files | `/updates` | `.ota` |
-| Screenshots (the Shell's `screenshot`) | `/screenshots` | `.png`, named by date and time |
+| [Screenshots](/howto/screenshot/) (<kbd>Fn</kbd> + <kbd>p</kbd>) | `/screenshots` | `.png`, named by date and time |
+| A VPN configuration waiting to be imported | `/vpn/wg0.conf` | you put it there; delete it once imported |
 
 ## Rules worth knowing
 

site/content/howto/vpn.md

@@ -0,0 +1,36 @@
++++
+title = "Set up the VPN"
+description = "Put a WireGuard configuration on the device with your phone, import it, and check that the tunnel is up."
+weight = 10
+[extra]
+tag = "VPN"
++++
+
+You need a WireGuard server, and a **client configuration** made on it for the Cardputer, as you would make one for a phone: a `.conf` file.
+
+1. Get the `.conf` onto the phone (or a computer on the same Wi-Fi), and name it **`wg0.conf`**.
+2. On the Cardputer, open **Storage** and press <kbd>w</kbd>; open the page on the phone ([Move files with your phone](/howto/phone-files/)).
+3. In the page, tap **New folder**, name it `vpn`, go into it, and **upload `wg0.conf`**.
+4. On the Cardputer, press Back to stop sharing.
+5. Open **Settings → VPN → Import /vpn/wg0.conf**. You should see "Imported", and a question: **delete the file**. Say yes: the configuration is now in the device, and the file still holds the private key in clear.
+6. Switch **VPN** to On. `VPN` appears in the Status Bar, and turns bright once the server has answered, usually within seconds. The page says "It is up".
+7. To have it start by itself, switch on **Start with Wi-Fi**.
+
+## Check it
+
+From another machine on the VPN, ping the Cardputer's tunnel address (the `Address` line of the file). Or on the device, in the [Shell](/guide/shell/): `vpn status`.
+
+## If it stays dim
+
+| The page says | Try |
+|---|---|
+| waiting for Wi-Fi | Connect to a network first |
+| waiting for the clock | Give it a moment after Wi-Fi connects: the time comes from the network |
+| looking up the server | The server's name doesn't resolve from this network |
+| no answer yet | The server's address or port, a firewall on the way, or the keys: check the server's side has this client's public key |
+
+## What goes through it
+
+Everything, if the file says `AllowedIPs = 0.0.0.0/0`; otherwise only the VPN's own subnet. To reach your home network behind the server, you need the first. See [VPN](/guide/vpn/#what-goes-through-it).
+
+**The upload in step 3 is not encrypted,** and the file holds a private key: do it on a network you trust, with a key made for this device.